scholarly journals Population Pharmacokinetics and Pharmacodynamics of Continuous versus Short-Term Infusion of Imipenem-Cilastatin in Critically Ill Patients in a Randomized, Controlled Trial

2007 ◽  
Vol 51 (9) ◽  
pp. 3304-3310 ◽  
Author(s):  
Samir G. Sakka ◽  
Anna K. Glauner ◽  
Jürgen B. Bulitta ◽  
Martina Kinzig-Schippers ◽  
Wolfgang Pfister ◽  
...  
Keyword(s):  
Continuous Infusion ◽  
Critically Ill ◽  
Critically Ill Patients ◽  
Drug Exposure ◽  
Population Pharmacokinetic ◽  
Beta Lactams ◽  
Target Attainment ◽  
Short Term ◽  
Randomized Controlled ◽  
Drug Concentrations

ABSTRACT Beta-lactams are regularly administered in intermittent short-term infusions. The percentage of the dosing interval during which free drug concentrations exceed the MIC (fT >MIC) is the measure of drug exposure that best correlates with clinical outcome for beta-lactams. Therefore, administration by continuous infusion has gained increasing interest recently. We studied 20 critically ill patients with nosocomial pneumonia and investigated whether continuous infusion with a reduced total dose, compared to the standard regimen of intermittent short-term infusion, results in a superior probability of target attainment as assessed by the fT >MIC value of imipenem. In this prospective, randomized, controlled clinical study, patients received either a loading dose of 1 g/1 g imipenem and cilastatin (as a short-term infusion) at time zero, followed by 2 g/2 g imipenem-cilastatin per 24 h as a continuous infusion for 3 days (n = 10), or 1 g/1 g imipenem-cilastatin three times per day as a short-term infusion for 3 days (total daily dose, 3 g/3 g; n = 10). Imipenem concentrations in plasma were determined by using a validated liquid chromatography-tandem mass spectrometry assay. A two-compartment open model was employed for population pharmacokinetic modeling. We simulated 10,000 intensive-care-unit patients via Monte Carlo simulations for pharmacodynamic evaluation using the target 40% fT >MIC. The probability of target attainment by MIC for intermittent infusion was robust (>90%) up to MICs of 1 to 2 mg/liter. The corresponding value for continuous infusion was 2 to 4 mg/liter. Although all 20 patients had an fT >MIC of 100%, 3 patients died. Patient survival was best described by employing a sepsis-related organ failure assessment score as a covariate in a logistic regression analysis. Larger clinical trials are warranted for evaluation of continuous infusions at a reduced dose of imipenem for critically ill patients.

scholarly journals Population Pharmacokinetics of Piperacillin following Continuous Infusion in Critically Ill Patients and Impact of Renal Function on Target Attainment

2020 ◽  
Vol 64 (7) ◽  
Author(s):  
Vibeke Klastrup ◽  
Anders Thorsted ◽  
Merete Storgaard ◽  
Steffen Christensen ◽  
Lena E. Friberg ◽  
...  
Keyword(s):  
Continuous Infusion ◽  
Critically Ill ◽  
Critically Ill Patients ◽  
Bacterial Infections ◽  
Population Pharmacokinetic ◽  
Target Attainment ◽  
Content Type ◽  
Daily Dose ◽  
Linear Elimination ◽  
Severe Infections

ABSTRACT Pharmacokinetic changes are often seen in patients with severe infections. Administration by continuous infusion has been suggested to optimize antibiotic exposure and pharmacokinetic/pharmacodynamic (PK/PD) target attainment for β-lactams. In an observational study, unbound piperacillin concentrations (n = 196) were assessed in 78 critically ill patients following continuous infusion of piperacillin-tazobactam (ratio 8:1). The initial dose of 8, 12, or 16 g (piperacillin component) was determined by individual creatinine clearance (CRCL). Piperacillin concentrations were compared to the EUCAST clinical breakpoint MIC for Pseudomonas aeruginosa (16 mg/liter), and the following PK/PD targets were evaluated: 100% free time (fT) > 1× MIC and 100% fT > 4× MIC. A population pharmacokinetic model was developed using NONMEM 7.4.3 consisting of a one-compartment disposition model with linear elimination separated into nonrenal and renal (linearly increasing with patient CRCL) clearances. Target attainment was predicted and visualized for all individuals based on the utilized CRCL dosing algorithm. The target of 100% fT > 1× MIC was achieved for all patients based on the administered dose, but few patients achieved the target of 100% fT > 4× MIC. Probability of target attainment for a simulated cohort of patients showed that increasing the daily dose by 4-g increments (piperacillin component) did not result in substantially improved target attainment for the 100% fT > 4× MIC target. To conclude, in patients with high CRCL combined with high-MIC bacterial infections, even a continuous infusion (CI) regimen with a daily dose of 24 g may be insufficient to achieve therapeutic concentrations.

scholarly journals Influence of Mechanical Ventilation on the Pharmacokinetics of Vancomycin Administered by Continuous Infusion in Critically Ill Patients

2017 ◽  
Vol 61 (12) ◽  
Author(s):  
Susanna Edith Medellín-Garibay ◽  
Silvia Romano-Moreno ◽  
Pilar Tejedor-Prado ◽  
Noelia Rubio-Álvaro ◽  
Aida Rueda-Naharro ◽  
...  
Keyword(s):  
Mechanical Ventilation ◽  
Creatinine Clearance ◽  
Continuous Infusion ◽  
Critically Ill ◽  
Critically Ill Patients ◽  
Population Pharmacokinetic Model ◽  
Pharmacokinetic Model ◽  
Volume Of Distribution ◽  
Stochastic Simulations ◽  
Population Pharmacokinetic

ABSTRACT Pathophysiological changes involved in drug disposition in critically ill patients should be considered in order to optimize the dosing of vancomycin administered by continuous infusion, and certain strategies must be applied to reach therapeutic targets on the first day of treatment. The aim of this study was to develop a population pharmacokinetic model of vancomycin to determine clinical covariates, including mechanical ventilation, that influence the wide variability of this antimicrobial. Plasma vancomycin concentrations from 54 critically ill patients were analyzed simultaneously by a population pharmacokinetic approach. A nomogram for dosing recommendations was developed and was internally evaluated through stochastic simulations. The plasma vancomycin concentration-versus-time data were best described by a one-compartment open model with exponential interindividual variability associated with vancomycin clearance and the volume of distribution. Residual error followed a homoscedastic trend. Creatinine clearance and body weight significantly dropped the objective function value, showing their influence on vancomycin clearance and the volume of distribution, respectively. Characterization based on the presence of mechanical ventilation demonstrated a 20% decrease in vancomycin clearance. External validation (n = 18) was performed to evaluate the predictive ability of the model; median bias and precision values were 0.7 mg/liter (95% confidence interval [CI], −0.4, 1.7) and 5.9 mg/liter (95% CI, 5.4, 6.4), respectively. A population pharmacokinetic model was developed for the administration of vancomycin by continuous infusion to critically ill patients, demonstrating the influence of creatinine clearance and mechanical ventilation on vancomycin clearance, as well as the implications for targeting dosing rates to reach the therapeutic range (20 to 30 mg/liter).

Early target attainment of continuous infusion piperacillin/tazobactam and meropenem in critically ill patients: A prospective observational study

2019 ◽  
Vol 52 ◽  
pp. 75-79 ◽  
Author(s):  
Sofie A.M. Dhaese ◽  
Alexander D.J. Thooft ◽  
Andras Farkas ◽  
Jeffrey Lipman ◽  
Alain G. Verstraete ◽  
...  
Keyword(s):  
Observational Study ◽  
Continuous Infusion ◽  
Critically Ill ◽  
Critically Ill Patients ◽  
Prospective Observational Study ◽  
Target Attainment

scholarly journals Model-Optimized Fluconazole Dose Selection for Critically Ill Patients Improves Early Pharmacodynamic Target Attainment without the Need for Therapeutic Drug Monitoring

2020 ◽  
Vol 65 (3) ◽  
Author(s):  
Indy Sandaradura ◽  
Jessica Wojciechowski ◽  
Deborah J. E. Marriott ◽  
Richard O. Day ◽  
Sophie Stocker ◽  
...  
Keyword(s):  
Therapeutic Drug Monitoring ◽  
Critically Ill ◽  
Drug Monitoring ◽  
Critically Ill Patients ◽  
Drug Exposure ◽  
Fungal Infections ◽  
Therapeutic Drug ◽  
Target Attainment ◽  
Dose Selection ◽  
Dose Individualization

ABSTRACT Fluconazole has been associated with higher mortality compared with the echinocandins in patients treated for invasive candida infections. Underexposure from current fluconazole dosing regimens may contribute to these worse outcomes, so alternative dosing strategies require study. The objective of this study was to evaluate fluconazole drug exposure in critically ill patients comparing a novel model-optimized dose selection method with established approaches over a standard 14-day (336-h) treatment course. Target attainment was evaluated in a representative population of 1,000 critically ill adult patients for (i) guideline dosing (800-mg loading and 400-mg maintenance dosing adjusted to renal function), (ii) guideline dosing followed by therapeutic drug monitoring (TDM)-guided dose adjustment, and (iii) model-optimized dose selection based on patient factors (without TDM). Assuming a MIC of 2 mg/liter, free fluconazole 24-h area under the curve (fAUC24) targets of ≥200 mg · h/liter and <800 mg · h/liter were used for assessment of target attainment. Guideline dosing resulted in underexposure in 21% of patients at 48 h and in 23% of patients at 336 h. The TDM-guided strategy did not influence 0- to 48-h target attainment due to inherent procedural delays but resulted in 37% of patients being underexposed at 336 h. Model-optimized dosing resulted in ≥98% of patients meeting efficacy targets throughout the treatment course, while resulting in less overexposure compared with guideline dosing (7% versus 14%) at 336 h. Model-optimized dose selection enables fluconazole dose individualization in critical illness from the outset of therapy and should enable reevaluation of the comparative effectiveness of this drug in patients with severe fungal infections.

scholarly journals Predictors of Inadequate Linezolid Concentrations after Standard Dosing in Critically Ill Patients

2016 ◽  
Vol 60 (9) ◽  
pp. 5254-5261 ◽  
Author(s):  
Max Taubert ◽  
Michael Zoller ◽  
Barbara Maier ◽  
Sebastian Frechen ◽  
Christina Scharf ◽  
...  
Keyword(s):  
Critically Ill ◽  
Critically Ill Patients ◽  
Strong Predictor ◽  
Simulated Patients ◽  
Population Pharmacokinetic ◽  
Target Attainment ◽  
Serum Samples ◽  
Time Curve ◽  
Blood Concentrations ◽  
Registration Number

ABSTRACTAdequate linezolid blood concentrations have been shown to be associated with an improved clinical outcome. Our goal was to assess new predictors of inadequate linezolid concentrations often observed in critically ill patients. Fifty-two critically ill patients with severe infections receiving standard dosing of linezolid participated in this prospective observational study. Serum samples (median, 32 per patient) were taken on four consecutive days, and total linezolid concentrations were quantified. Covariates influencing linezolid pharmacokinetics were identified by multivariate analysis and a population pharmacokinetic model. Target attainment (area under the concentration-time curve over 12 h [AUC12]/MIC ratio of >50; MIC = 2 mg/liter) was calculated for both the study patients and a simulated independent patient group (n= 67,000). Target attainment was observed for only 36% of the population on both days 1 and 4. Independent covariates related to significant decreases of linezolid concentrations included higher weight, creatinine clearance rates, and fibrinogen and antithrombin concentrations, lower concentrations of lactate, and the presence of acute respiratory distress syndrome (ARDS). Linezolid clearance was increased in ARDS patients (by 82%) and in patients with elevated fibrinogen or decreased lactate concentrations. In simulated patients, most covariates, including fibrinogen and lactate concentrations and weight, showed quantitatively minor effects on target attainment (difference of ≤9% between the first and fourth quartiles of the respective parameters). In contrast, the presence of ARDS had the strongest influence, with only ≤6% of simulated patients reaching this target. In conclusion, the presence of ARDS was identified as a new and strong predictor of insufficient linezolid concentrations, which might cause treatment failure. Insufficient concentrations might also be a major problem in patients with combined alterations of other covariate parameters. (This study has been registered at ClinicalTrials.gov under registration number NCT01793012.)

scholarly journals Continuous Infusion Compared with Intermittent Intravenous Infusion of Beta-Lactam Antibiotics for Critically Ill Patients: A Systematic Review and Meta-Analysis of Randomized Trials

2020 ◽  
Author(s):  
Chien-Huei Huang ◽  
Ching-Yao Shih ◽  
Meng Keng Tsay ◽  
Shen-Pei Hsuan ◽  
Yung-Hsin Tseng ◽  
...  
Keyword(s):  
Continuous Infusion ◽  
Critically Ill ◽  
Critically Ill Patients ◽  
Eradication Rate ◽  
Cochrane Library ◽  
Secondary Outcome ◽  
Bacterial Eradication ◽  
Beta Lactam ◽  
Beta Lactams ◽  
Beta Lactam Antibiotics

Abstract Background: The pathophysiologic changes during critical illness and high minimal inhibitory concentration (MIC) pathogens are important risk factors of mortality and bacterial eradication in critical care. Beta-lactam antibiotics have a time-dependent effect on bactericidal activity. The continuous infusion (CIF) of beta-lactam antibiotics achieves sufficient drug concentration above the MIC, especially for critically ill patients. However, the superiority of CIF over intermittent infusion (IIF) of beta-lactam antibiotics is yet to be clearly established. Thus, we aimed to investigate the effects on mortality of CIF of beta-lactams antibiotics in comparison to those of IIF of beta-lactams antibiotics in patients with sepsis admitted to the intensive care unit (ICU).Methods: We systematically searched PUBMED, MEDLINE, Cochrane Library, EMBASE, Web of Science, and ICTRP for randomized controlled trials (RCTs) comparing CIF with IIF of beta-lactam antibiotics in critically ill populations. All RCTs published until October 2019 were eligible. The primary outcome measure was the relative risk (RR) of mortality, while the secondary outcome measures were bacterial eradication rate, length of ICU stay, and length of admission. Results: In total, 6 RCTs comprising 974 patients were analyzed. We found a significantly lower mortality for critically ill patients on CIF (RR: 0.79; 95% CI: 0.63, 0.98) compared with those on IIF of beta-lactam antibiotics. The pooled RR for the bacterial eradication rate was 1.16 (95% CI: 1.03, 1.29) for CIF compared with IIF administration. Conclusion: CIF of beta-lactam antibiotics for critically ill patients significantly reduces mortality and yields a better bacterial eradication rate than IIF. These findings support the clinical and bacterial eradication benefits in adult critically ill patients, and may guide clinical discussions and decisions.

Sign in / Sign up

Export Citation Format

Share Document